Continuous monitoring of esophageal motor function, lower esophageal sphincter pressure and esophageal pH as performed in subjects with sporadic episodes of gastroesophageal reflux are compared to normal volunteers. The importance of swallowed saliva in esophageal acid clearance is also examined. Lower esophageal sphincter relaxation and abnormal esophageal reflux in patients with gastroesophageal reflux and other disorders are examined.